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3.28.10 H

 
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Ema Nymton



Joined: 17 Apr 2009
Posts: 89

PostPosted: Sun Mar 28, 2010 10:17 pm    Post subject: 3.28.10 H Reply with quote

.

No solution:

Code:

+----------------+-------------+--------------+
| 137  137   134 | 134 5   8   | 9    6   2   |
| 1358 12358 6   | 7   9   123 | 38   4   58  |
| 9    2358  234 | 6   34  23  | 1    37* 578 |
+----------------+-------------+--------------+
| 4    9     123 | 5   8   37  | 27   127 6   |
| 13   123   8   | 34  347 6   | 5    127 9   |
| 56   56    7   | 2   1   9   | 4    8   3   |
+----------------+-------------+--------------+
| 3678 3678  5   | 38  237 4   | 2378 9   1   |
| 1378 4     9   | 138 237 5   | 6    237 78  |
| 2    1378  13  | 9   6   137 | 378  5   4   |
+----------------+-------------+--------------+


Draw/Play gives as a hint, '7' at r3c8.
Is it possible for one to show why?

Ema Nymton
~@:o|
.
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Sun Mar 28, 2010 11:30 pm    Post subject: Reply with quote

Code:
+----------------+-------------+--------------+
| 137  137   134 | 134 5   8   | 9    6   2   |
| 1358 12358 6   | 7   9   123 | 38   4   58  |
| 9    2358 *234 | 6  *34 *23  | 1    37  578 |
+----------------+-------------+--------------+
| 4    9     123 | 5   8   37  | 27   127 6   |
| 13   123   8   | 34  347 6   | 5    127 9   |
| 56   56    7   | 2   1   9   | 4    8   3   |
+----------------+-------------+--------------+
| 3678 3678  5   | 38  237 4   | 2378 9   1   |
| 1378 4     9   | 138 237 5   | 6    237 78  |
| 2    1378  13  | 9   6   137 | 378  5   4   |
+----------------+-------------+--------------+

In row 3 the "starred cells are a naked triple. They use up all the 2s, 3s, and 4s in row 3. The cell that had the hint 7 cannot be a 3, thus is 7.
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Mogulmeister



Joined: 03 May 2007
Posts: 1151

PostPosted: Sun Mar 28, 2010 11:45 pm    Post subject: Reply with quote

Hi Ema,

Well you can look at it two ways:

a)TRIPLE

Notice in Row 3 that cell 3 is <234> cell 5 is <34> and cell 6 is <23>
Together they form a triple: three cells, three numbers and only those numbers. This means they belong to those cells alone and you can therefore eliminate 2,3,4 from any other cells in row 3. Result is that 3 is removed from the cell you have highlighted leaving 7.

b)PAIR

There is also a hidden pair in row 3. Look at cell 2 and cell 9 they both have 5,8 in them. 5,8 occurs nowhere else in the row. This makes them a locked pair - they can only be in cells 2 and 9. This eliminates the 2,3 from cell 2 and the 7 from cell 9.

There is now only a 7 left in cell 8.

Hope this helps.

(apologies to wapati -see what happens when you take a call in mid-post!!)
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Ema Nymton



Joined: 17 Apr 2009
Posts: 89

PostPosted: Mon Mar 29, 2010 9:05 am    Post subject: Reply with quote

.

Mogulmeister wrote:
Hi Ema,

Well you can look at it two ways:

a)TRIPLE

Notice in Row 3 that cell 3 is <234> cell 5 is <34> and cell 6 is <23>
Together they form a triple: three cells, three numbers and only those numbers. This means they belong to those cells alone and you can therefore eliminate 2,3,4 from any other cells in row 3. Result is that 3 is removed from the cell you have highlighted leaving 7.

b)PAIR

There is also a hidden pair in row 3. Look at cell 2 and cell 9 they both have 5,8 in them. 5,8 occurs nowhere else in the row. This makes them a locked pair - they can only be in cells 2 and 9. This eliminates the 2,3 from cell 2 and the 7 from cell 9.

There is now only a 7 left in cell 8.

Hope this helps.

(apologies to wapati -see what happens when you take a call in mid-post!!)


Phenomenal. The subtlety of the solution is impressive.

Thank you.

Ema Nymton
~@:o)
.
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